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Adaptive implementation of an optimal time-varying filter (TVF) for evoked potential (EP) estimation is addressed in this paper. A data-adaptive scheme is used, which converges asymptotically to the optimal TVF solution. Two basic adaptive TVF's (ATVF's) are first introduced, namely least mean square (LMS) ATVF and recursive least-squares (RLS) ATVF. The latter converges much faster than the former. Since the basic ATVF's usually require a relatively large set of response trials to get a meaningful solution, a reduced-order ATVF is further presented and the corresponding LMS and RLS (including a fast RLS) adaptive algorithms are developed. To save memory, a truncated Fourier expansion is suggested to express approximately the time-sequenced weight-vectors of the ATVF's, resulting in a simplified reduced-order ATVF. Finally, extensive simulations are provided to confirm the superior performance of the ATVF's. The present ATVF's can be used as prefilters for latency-corrected average (LCA) processing to obtain more informative estimates of EP signals.

A peak component latency-corrected average (PC-LCA) method consisting of three steps is presented for estimating the evoked potentials (EP) in the human brain. The present PC-LCA is essentially an alternative version of the original LCA method developed by McGillem et al. It first uses a time-varying adaptive filter as a preprocessor to suppress the ongoing EEG and to enhance the EP. Then, the statistics of mean latencies and amplitudes of the EP peak components are estimated by a peak detection and alignment procedure. The final waveform estimate is obtained by superimposing the estimated mean peak components on background information and subsequently fitting a truncated Fourier series using the fast Fourier transform (FFT). Consistent estimates of the EP peak component information are established based on asymptotic analysis of the PC-LCA. Finally, real-time implementation of the PC-LCA is considered, and the superior performance of the PC-LCA method is confirmed by detailed numerical results.

The goal of the present neuroanatomical study in macaque monkeys was twofold: (1) to clarify whether the hand representation of the primary motor cortex (M1) has a transcallosal projection to M1 of the opposite hemisphere; (2) to compare the topography and density of transcallosal connections for the hand representations of M1 and the supplementary motor area (SMA). The hand areas of M1 and the SMA were identified by intracortical microstimulation and then injected either with retrograde tracer substances in order to label the neurons of origin in the contralateral motor cortical areas (four monkeys) or, with an anterograde tracer, to establish the regional distribution and density of terminal fields in the opposite motor cortical areas (two monkeys). The main results were: (1) The hand representation of M1 exhibited a modest homotopic callosal projection, as judged by the small number of labeled neurons within the region corresponding to the contralateral injection. A modest heterotopic callosal projection originated from the opposite supplementary, premotor, and cingulate motor areas. (2) In contrast, the SMA hand representation showed a dense callosal projection to the opposite SMA. The SMA was found to receive also dense heterotopic callosal projections from the contralateral rostral and caudal cingulate motor areas, moderate projections from the lateral premotor cortex, and sparse projections from M1. (3) After injection of an anterograde tracer (biotinylated dextran amine) in the hand representation of M1, only a few small patches of axonal label were found in the corresponding region of M1, as well as in the lateral premotor cortex; virtually no label was found in the SMA or in cingulate motor areas. Injections of the same anterograde tracer in the hand representation of the SMA, however, resulted in dense and widely distributed axonal terminal fields in the opposite SMA, premotor cortex, and cingulate motor areas, while labeled terminals were clearly less dense in M1. It is concluded that the hand representations of the SMA and M1 strongly differ with respect to the strength and distribution of callosal connectivity with the former having more powerful and widespread callosal connections with a number of motor fields of the opposite cortex than the latter. These anatomical results support the proposition of the SMA being a bilaterally organized system, possibly contributing to bimanual coordination.

Cerebral hypoxia-ischemia was produced in 7 day old rats by right common carotid artery occlusion combined with systemic hypoxia. In the hypoxic-ischemic group animals, striatal ACh contents on both sides were reduced to a significant extent in commensurate to AChE histochemical image analysis. All these changes could be restored to normal control by a protection dose (50 micrograms) of NGF intraventricularly injected.

Organ cultures of 15-day embryonic mouse metatarsals cultured in serumless, chemically-defined medium were used to investigate the influence of 1 alpha,25-dihydroxyvitamin D3 (1,25(OH)2D3) on calcitonin receptor (CTR) expression in osteoclasts formed from in situ progenitors. CTR expression was demonstrated in tartrate-resistant acid phosphatase-positive (TRAP+) osteoclasts and their precursors. The expression of TRAP preceded that of CTR and was first observed in cells identified as osteoclast precursors. Not all TRAP+ precursors were CTR+ and from 40 to 60% of newly formed osteoclasts lacked CTR. Treatment with 1,25(OH)2D3 increased precursor numbers without affecting CTR expression, whereas both the numbers and the percentage of newly formed osteoclasts expressing CTR was increased by 1,25(OH)2D3. Grain count analysis revealed that this increased percentage of newly formed CTR+ osteoclasts were cells with low and medium levels of CTR expression. This apparent down-regulation of CTR expression in newly formed osteoclasts may help to explain the 'escape' of osteoclastic bone resorption from the inhibitory effects of calcitonin.

Smooth muscle and several non-muscle tissues contain mRNA for an alternative splice of the mRNA for the cardiac sarcoplasmic reticulum (SR) Ca,Mg-ATPase. Based on amino acid composition deduced from cDNA sequences the cardiac isoform (Ic) is 110 kDa while the smooth muscle and the non-muscle isoform (Is) is 115 kDa. This prediction in their molecular masses was tested at the protein level in rabbit stomach, aorta, uterus and vas deferens smooth muscles; stomach mucosa, brain, liver, kidney and heart. The major species of the acylphosphates formed in the presence of Ca2+ and electrophoresed in acid SDS-acrylamide gels were 5 kDa smaller for the heart (Ic) than those for all the other tissues (Is). The size difference was also confirmed in Western blots using a monoclonal antibody which binds to both Is and Ic. Thus consistent with the mRNA splices for the internal Ca2+ pumps previously reported to be present in these tissues, rabbit heart expresses predominantly the Ca2+ pump protein Ic and the various smooth muscle, mucosa, brain, liver and kidney express mainly the isoform Is.

An in vitro model system is described, using metatarsal explants from 15-day mouse embryos (E15) cultured in serumless chemically defined medium, to study fetal skeletal development with particular emphasis on de novo osteoclast formation. The normal pattern of growth and differentiation observed in vitro, assessed by ultrastructure and morphometry, demonstrate a permissive local environment which replicates physiologic temporal and spatial relationships which exist in vivo. The population of committed osteoclast progenitors present in E15 metatarsals form osteoclasts and precursors which have cytochemical and ultrastructural features, as well as kinetics of formation, that are similar to that which occurs in vivo. The responsiveness of osteoclast formation to the effects of added 1,25(OH)2D3 illustrates that controlled manipulation enables one to exploit the system for investigating the role of cytokines, growth factors and osteotropic hormones in skeletal development and osteoclast ontogeny.

The surface structure of Clonorchis sinensis cercariae was observed under scanning electron microscope. The cercaria was of the parapleuro-lophocercous type. The measurements of the cercariae were as follows: body 137-240 x 62-90 microns, tail 320-470 x 21-34 microns, oral sucker 27-46 x 23-33 microns. The ventral sucker was incompletely developed and much smaller than the oral one. The whole body surface was covered with backward pointing spines. Four horizontal rows of oral spines were found around the mouth opening of the oral sucker. These spines diminished in size with the distance of the rows from the opening and their numbers were 12, 18, 19 and 18 respectively. Transverse and longitudinal plicae formed from tegument were found on the surface of the tail, being in connection with dorsal and ventral fins along posterior half of the tail. Many sensory structures or papillae were observed on the body. They were of three different types: 1) papillae with long or short cilia distributed widely on the body surface and around the mouth opening, the number of papillae with cilia on the body surface being greater than that described by Komiya et al (1940); 2) a few sensory fossa on the tail, measuring 1.0 x 0.6 microns; 3) a few ring-type papillae with knob on the body surface with pore of 0.5 micron in diameter.

This study shows that nimodipine significantly reduces levels of blood pressure in patients with mild and moderate essential hypertension. Hypotensive efficacy is less than with nifedipine, but side effects are light, and the drug is shown to reduce serum Na+ and cholesterol and there is regression of LVH (ECG).

The effect of albendazole on the body wall and gut of Clornorchis sinensis was studied with transmission and scanning electron microscopes after albendazole administration to rats infected with Chonorchis sinensis at a single dose of 150 mg/kg. The results showed that swelling and adhesion of the projections of the tegument and gut microvilli occurred 1h after medication. Necrosis and disruption of the projections and the gut microvilli were seen at the 24th h. By the 72nd h, detachment of the partial projections were seen. The dynamic process of the damages observed on the tegument was identical with that of the gut microvilli (Figs. 1-10).

7 alpha-bis (beta-chloroethyl) aminomethyl-6, 14-endoetheno-tetrahydro oripavine (alpha-CAM) is a new irreversible opioid receptor agonist. Its effect on isolated tissues (guinea pig ileum, mouse vas deferens, rat vas deferens and rabbit vas deferens) were studied. It was shown to be bound irreversibly to rat brain P2 membrane preparations. The ED50 of its analgesic effect in mice (icv) was found to be 0.12 nmol/mouse, and the effect may last as long as 2-3 days. It is a compound which produces the longest analgesia known up to date. A single dose (icv) of alpha-CAM was sufficient to produce dependence in mice. Thus, the compound may serve as an agent for studying the mechanism of physical dependence.

A study of hard tissue and soft tissue contour and growth on normal occlusion among Chinese population was made by means of computerized radiographic cephalometrics. Correlation analysis and polygon methods were applied to analyse the profile contour. The result showed that the dento-skeletal pattern and integumental contour were not necessarily alike, the diversity could be quite prominent. As to the growth change features in soft-tissue and hard-tissue structure, we found that the growth behavior of the lips seemed to show a tendency to follow the dental structure directly. The bony profile tended to become less convex with aging, while the soft-tissue profile remained stable in its degree of convexity.

Between March and August 1986 in Huangshi City, serum samples were collected from 316 apparently healthy barbers as a study group, as well as from 361 healthy employees of department stores as a control group. They were tested for hepatitis B surface antigen (HBsAg), antibody to HBsAg (anti-HBs) and antibody to hepatitis B core antigen (anti-HBc) by enzyme-linked immunoadsorbent assays. Barbers showed a prevalence higher than that in controls for HBsAg (16.8 vs. 9.2%, P less than 0.01), anti-HBs (67.1 vs. 45.9%, P less than 0.001), and anti-HBc (39.2 vs. 21.2%, P less than 0.001). The prevalence of at least one marker of hepatitis B virus (HBV) infection was significantly higher in barbers than in controls (86.1 vs. 61.7%, P less than 0.001). Although the socioeconomic status and education level did not correlate with the frequency of HBV markers, the prevalence of HBsAg increased in parallel with the duration of practice. Because of their high risk for HBV infection, barbers need to be screened for markers of HBV infection on a routine basis, and are prime candidates for immunoprophylaxis with hepatitis B vaccine.

7 alpha-Bis (beta-chloroethyl)amino-methyl-6,14-endoethenotetrahydrooripavine (alpha-CAM) was found to bind to opioid receptors irreversibly and react directly with sulfhydryl (SH) groups in P2 preparations of rat brain. The P2 preparations were pretreated as follows: protection of the SH groups at the opioid receptor binding sites by morphine or etorphine, and inactivation of the SH groups outside the binding sites by N-ethylmaleimide (NEM), followed by removal of the morphine or etorphine by washing. alpha-CAM was still able to bind the pretreated P2 preparations in an irreversible manner. The results indicate that the formation of covalent bonds between alpha-CAM and the SH groups of opioid receptor binding sites is possibly one of the biochemical mechanisms of the irreversible action of alpha-CAM.